Soldiers stand guard at the tomb of Suleyman Shah in 2011.AP

For years, as the civil war in Syria has raged on its border, Turkey has maintained a careful remove. As foreign soldiers made their way to fight on behalf of countless groups in Syria, the government sat on its hands. Even when ISIS and Kurdish fighters were engaged in a pitched battle just over the border in Kobani, the Turks studiously stuck to observation. During the past weekend, though, the Turkish army swung into action and sent troops into Syria. What inspired the sudden shift?

The Turkish operation, it turns out, was to rescue the tomb of Suleyman Shah. The tomb is a bizarre aberration, a piece of Middle Eastern history that ties the region and modern Turkey back to the dying days of the Ottoman Empire and, even further back, to the prehistory of the dynasty. And the mission to relieve it shows the nexus of Turkey's nationalist military and its Ottoman-revivalist Islamist government, and illustrates the president's fondness for skulduggery.

Suleyman Shah was a tribal leader in the 13th-century Levant, and the grandfather of Osman I, the founding patriarch and namesake of the Ottoman Empire. He is believed to have drowned in the Euphrates in 1236, and was buried in what is now Syria. In 1886, Sultan Abdul Hamid II had a tomb rebuilt on what was believed to be the grave of his ancestor (although it very possibly wasn't). After World War I, the Western powers broke up the Ottoman Empire and the French took control of Syria. They fought a brief war with the new Turkish state, then signed a peace treaty that, in part, gave the Turks control over Suleyman Shah:

The tomb of Suleiman Shah, the grandfather of the Sultan Osman, founder of the Ottoman dynasty (the tomb known under the name of Turk Mezari), situated at Jaber-Kalesi shall remain, with its appurtenances, the property of Turkey, who may appoint guardians for it and may hoist the Turkish flag there.

That agreement held until 1973, when the building of the Tabqa Dam threatened to flood the tomb's location. As a result, it was moved 50 miles north, which is where it was until this weekend. The legal status of the tomb remained in dispute. Turkey claimed it as an exclave, arguing that the location was sovereign Turkish territory, while Syria disagreed.

That dispute became hotter as the Syrian civil war erupted, especially after the Syrians and Turks shot down each other's aircraft. In 2014, ISIS troops neared the tomb and demanded that Turkey evacuate; then-Prime Minister Recep Tayyip Erdogan warned that any attack would meet with retribution: "The tomb of Süleyman Şah and the land surrounding it is our territory. We cannot ignore any unfavorable act against that monument, as it would be an attack on our territory, as well as an attack on NATO land." The usual force of conscripts garrisoned at Suleyman Shah was replaced by more hardened troops.

Then, a recording leaked of top Turkish officials discussing what appeared to be the prospect of a false-flag attack on the tomb that could be used as a pretext to launch military operations in Syria—a "wag-the-dog" style attack that could help boost Erdogan's chances in the 2014 presidential election. It was one of several embarrassing leaks that led the Turkish government to try to block both YouTube and Twitter.

In the event, ISIS didn't attack and neither did the Turks, and Erdogan handily won the election. But the 38 soldiers at the tomb were stuck, effectively held hostage. And so on Saturday night, hundreds of Turkish soldiers along with heavy equipment pushed the 15 or so miles into Syria and broke them, and the tomb, out of the country. They removed the remains and rescued the garrison. Although they didn't encounter any armed resistance, one Turkish soldier was apparently killed in an accident.

What exactly was done with the remains is uknown. Reuters quoted Prime Minister Ahmet Davutoglu as saying: "The remains of Suleyman Shah, along with ancestral relics, have been brought back to our country pending their temporary transfer to a new site in Syria." Yet CNN quoted the Turkish Foreign Ministry as saying that they had been moved to a village even closer to the border but still in Syria—establishing the third location of the alleged remains and effectively claiming a new, third location for their exclave—and the BBC published photos of Turkish soldiers raising the flag at the new location. In any case, Turkish officials vowed to return Suleyman Shah's tomb to its post-1973 location and said they continued to claim the land.

Turkish army bulldozers at the new site of Suleyman Shah's tomb, near the border but inside Turkey. (Reuters)

None of this went over well with Bashar al-Assad's Syrian government, which was livid about the incursion. Syrian officials also suggested that Turkey is colluding with ISIS, noting as evidence that the group had abstained from attacking the tomb site. “Turkey went far beyond providing all forms of support to its tools of the gangs of ISIS, Jabhat al-Nusra and other al-Qaeda-linked terrorist organizations to carry out a blatant aggression on the Syrian territory,” a government source told SANA, the official news agency.

Ever since Mustafa Kemal created modern Turkey as a secular nation, the country has grappled with a tension between militaristic nationalism and a more traditional, religious sense of identity. Often, when the power of the more religious camp grows, the military has stepped in to reimpose Kemalism. Recently, though, Erdogan's Islamist movement seems to have gained a definitive upper hand. The Erdogan era has also ushered in a new nostalgia for the lost empire—Ottomania. Manifestations of that trend range from the wildly popular soap opera Magnificent Century set in the Ottoman era, to plans to build a mall in an Istanbul park that mimics a long-demolished Ottoman barracks. (That plan was the flashpoint for massive protests in Istanbul in 2013.)

The Suleyman Shah raid, journalist Cengiz Candar notes, is on the one hand a feather in the cap of the Turkish military, and an example of Erdogan and the army's harmony. On the other hand, some nationalists are furious at what they see as a surrender of Turkish territory.

This sort of turbulence is in keeping with the sad tale of the tomb, which has been more of a political symbol than a mausoleum since at least the days of Abdul Hamid II. Based on this week's events, a permanent resolution isn't in the offing any time soon—so almost 800 years after his death, Suleyman Shah still can't rest in peace.

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